Or, short of what I've dreamed up above, is there an easy way to have results displayed by github's org file renderer, so the following would be visible (ideally with formatting that I specify at the document level):

Interesting idea, but I don't think there's anything ready-made. I'd try to modify the specific Babel backend to place results in the predetermined place. Though this seems complicated, when the results have multiple lines for example.
– wvxvwMar 27 '16 at 12:51

Thanks. This is a helpful approach and seems flexible enough to allow formatting of the results in whatever way I want. But, I think it (like my own solution) is too verbose to be convenient for quick notes or blog posts, which is what I was hoping to find. Perhaps some modifications to babel building on this functionality could get me there, though.
– parkeristypingApr 4 '16 at 22:41

1

@parkeristyping - I agree. It's much too verbose. If it's something I going to do fairly often, e.g. blog, I usually write some template code to generate the formatted org code in step 2. Then I just update a variable passed into the template generator, e.g. :var my_code='("my-code" "my-other-code"). Even so it's still more cumbersome than I would like. Would you like me to update my answer?
– MelioratusApr 4 '16 at 23:02

@parkeristyping - I just figured out another way but it requires that you export the original org file and post the export to GitHub.
– MelioratusApr 4 '16 at 23:11

This returns the following on C-c C-c, which does display on github due to the :exports both header, but it's in a separate code block.

#+RESULTS:
#+BEGIN_SRC scheme
;=> 12
#+END_SRC

I think this strategy leaves the org file too cluttered to be worth it, though. And, unless I disable the code evaluation confirm, I have to accept two "Are you sure you want to evaluate code?" prompts (one for the Scheme block and one for the elisp commentify).